Automatic inflating devices are known which are comprised of a single base body into which a pressure gas bottle sealed with a diaphragm and constructed in the form of a cartridge is screwed. A spring element is located inside the device which, by the screwing in of the cartridge or by being fitted together, is tensioned and produces the requisite momentum force in order to, with the aid of a pertinent lever drive, subsequent to the interposition of a water-soluble tablet, drive a pointed cutter through the sealing diaphragm for the purpose of opening the pressure gas bottle.
In the known device, the actual opening means with the cutter and the releasing part equipped with the tablet are fixedly integrated into the base body. This means that the individual components together form a mechanical unit which, both in construction and manufacture, is comparatively expensive. This also applies in particular to the cutter which is integrated into the tensioning mechanism and has to be acted upon by a separate spring element in such a way that, when the mechanism is tensioned, the diaphragm is not inadvertently pierced by the introduction of the cartridge.
The technical problem of the invention is to provide a device of the type stated in the beginning which is distinguished by a simplified construction and which permits in particular the employment of a greatly simplified and very inexpensive cutter.